Panel mounting system



Aug-22,1967 I H. H.AST 3,337,076

I PANEL MOUNTING SYSTEM Original Filed Dec. 28, 1962 4 Sheets-Sheet 1FEE-resem- 7- INVENTOR WL AJZ, f flsau,

ATTORNEYS Aug. 22, 1967 H. H. AST

PANEL MOUNTING SYSTEM 4 Sheets-Sheet 2 Original Filed Dec. 28, 1962 T mS R s & m A W M a w a 1 w fi m fi llll 11 l W m m u a i n W T g. m l 2 ATTOIZN EYS Aug. 22, H. H. AST

PANEL MOUNTING SYSTEM Original Filed Dec. 28, 1962 4 Sheets-Sheet 3 aF-fis-zasrz-r fien- INVENTOR.

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ATTQZHEY? Aug. 22., 1967 Original Filed Dec. 28, 1962 H H. AST 3,337,076

PANEL MOUNTING SYSTEM 4 SheetsSheet FEEPBEE'T P5. @57- INVENTOR.

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W Z M United States Patent 3,337,076 PANEL MOUNTING SYSTEM Herbert H.Ast, 1361 Berea Place, Pacific Palisades, Calif. 90272 Originalapplication Dec. 28, 1962, Ser. No. 247,942. Divided and thisapplication Oct. 24, 1965, Ser. No. 504,913

2 Claims. (Cl. 2203.6)

This invention relates to mounting means and more particularly tosystems for mounting components such as electrical switching assemblies,and the like on planar panel members.

This application is a divisional of my copending application Ser. No.247,942, filed Dec. 28, 1962, now Patent No. 3,253,275.

In modern control and monitoring systems such as utilized, for example,in missile control complexes, radar control centers, automatedindustrial systems, building complex air conditioning, airborne andshipboard maintenance and guidance systems, nuclear reactors, and thelike, it is generally desirable and often essential that a large numberof monitoring indicator lamps and control switches and other suchcomponents be arranged at a particular, single location. It is notuncommon for such a system to require many hundreds of indicationfunctions and sequences of functions with a large number of associatedswitching or control functions. Typically, a number of multicolorindicator units are mounted in an appropriate array on a display-controlpanel with each unit labeled as by a transparent frontal legend plate todesignate which item or function it is monitoring. It is then capable ofilluminating the legend plate with any one of a plurality of colorsoflight to denote the particular state or states of the item monitored.

Typically the identity and color of illumination of a particularindicator unit constitute an instruction for a particular action; forexample, Inert #4 Control Rod or Fire Missile D. Pressing the legendplate of the indication unit then automatically initiates the indicatedaction.

It is inherent in such an indicator unit that a relatively complexassembly of indicator lamps, switches, wires, and wire connections arerequired to achieve the desired indicator and switch capabilities. It isobvious, furthermore, that miniaturization is highly desirable in orderto minimize the required panel space and optical scanning area for thehuman operator.

Attempts heretofore to provide miniaturization and compactness ofmulticolor indicator-actuators have resulted in units which arecompromised in reliability and durability and which at the same time aremechanically difficult to service and maintain. Generally, special toolsare required to replace burned out lamps, and in the process ofrelamping, loose parts are vulnerable to loss and inadvertentinterchange, as of legend plates or colors of bulb color filters.Obviously any such error in reassembling the unit could have gravelyserious consequences regarding the operation of the system. Prior artsystems typically cause the existence of loose parts during servicingbecause, for example, the conventional colored plastic covers or filtersfor the lamps must be removed when the lamp is removed. Typically, also,the

legend plate is removed in order to provide access to the lamps.

Other shortcomings of prior attempts to provide a compact, reliableindicator assembly are that even the better of these have resulted inunits which create heat dissipation problems, are difiicult andexpensive to manufacture and install, and require a large depth behindthe mounting panel either because of the depth of the unit or becauseservicing and installation wiring must be done from the rear of theunit. In addition, such units are not environment-proof regarding dustand moisture, and do not provide an intense, even illumination acrossthe legend plate, but rather are generally dim with hot" spots on theindicator face. Prior art attempts to provide brilliant, evenillumination have typically been directed toward larger and morepowerful lamps. However, such attempts aggravate the heat dissipationproblems in a large panel and create a thermal stress on other elementsof the indicator units thereby decreasing the overall reliability.

It has been the practice in accordance with the better prior indicatorart to double lamp each color with two lamps in parallel in order to aidthe operator in distinguishing a burned out lamp from a proper lack ofenergization of a particular color in a unit. However, the problem ofachieving even distribution of illumination over the legend plate evenwith two bulbs without overheating and hot spotting has been difficultto solve; and heretofore there has not been available a double lampedunit which has even a reasonably satisfactory illumination when one lampis burned out. Typically, the illumination is not even and is notintense enough to be noticed in an environment of usefully ambient lightsuch as an airplane cockpit.

Another area of deficiency in the prior art is the switching actionachieved by depressing the legend plate. Typically, relamping of priorart devices inherently causes a switching action when the unit isreassembled. In addition their construction is such as to cause them tobe Vulnerable to accidental actuation when the operator inadvertentlytouches or brushes the panel or is thrown thereagainst due to vehicle orship acceleration.

In addition when the switch is actuated, the lamps and their contactsare jarred or accelerated thus alfecting their reliability due tocontact strain or filament breakage.

A final area of prior art deficiency, the curing of which is an objectof the present invention, is that of the inconvenience and labor costsin installing the prior art multicolor indicator-actuator units. Suchdevices typically require solderingof connections and other activitiesbehind the mounting panel and require time of the order of an hour todrill holes, mark, remove, and resolder leads. and check out the hookupwhen a unit is installed or replaced.

Specifically, it is an object of the present invention to provide acompact, reliable, multicolor, double lamped indicator-actuator assemblywhich is not subject to these and other disadvantages of the prior art.

It is another object to provide such a unit which is an integralassemblyv and which capitively holds all parts during lamp testing andrelamping procedures.

It is another object to provide such a unit which exhibits an even andvivid brilliance over the entire legend plate regardless of lamp burnoutor lamp color.

It is another object of the invention to provide such a double lampedunit which has a useful, even brilliance when only one lamp is energizedthus enabling a double number of indication functions, when desired, byvirtue of two levels of brilliance for each color or a double number ofcolors because only one bulb is needed for a full, even brilliance.

It is another object of the invention to provide such a double lampedunit which may be plugged into the panel from the front withoutsoldering of connections on the unit.

It is another object of the invention to provide such a double lampedunit which may be relamped without removal of lamp color filters fromtheir place in the unit.

It is another object of the invention to provide such a unit in whichrelamping may be achieved and legend plates changed without switchactuation.

It is another object of the invention to provide such a unit whichdirects the lamp heat out of the unit into the environmental space.

It is another object of the invention to provide such a unit which issubstantially sealed and environment proof.

It is another object of the invention to provide such a unit which is atleast 100% shorter in depth than doublelar'nped multicolor switchindicators heretofore available.

It is another object of the invention to provide such a unit which isnot vulnerable to accidental switch actuation.

It is another object of the present invention to provide such a unit inwhich the lamp filaments and the lamp contacts do not sufferacceleration or relative movement, respectively, during switchactuation.

Briefly, these and other objects and advantages are achieved in oneexample of the present invention in which a lamp holder member isprovided having a frontally relieved region which defines a reflectorcup into which three lamp envelopes project laterally inwardly towardeach other from each of two opposite sides. Each of the six bulbs isretained in one of six parallel bores communicating through the oppositesides of the member into the reflector cup. Within each bore at apredetermined distance from the 'side of the member, a retainingshoulder is disposed. A colored plastic filter cap is placed with itsbase lip against the shoulder and its cylindrical body extending throughthhe remainder of the bore into the reflector cup. An outwardly biasing,short coil spring is placed against the base lip in a manner to extendtoward the side of the lamp holder member.

A conventional miniature indicator lamp may then be inserted through thebore from the side, radially within the coil spring and the retainingshoulder, and into the plastic filter cap. The mounting shoulder aboutthe base of the lamp is received by the bore and engages the end of thecoil spring which urges the central contact point of the lamp outwardlyslightly beyond the side of the lamp holder member for positiveelectrical contact with other conductors.

The reflector cup is a highly reflective surface with elemental surfaceportions cooperatively contoured behind, between, and forwardly of thelamp envelopes to distribute the light from any one bulb to all portionsof the frontal area of the reflector cup.

The invention includes mounting structure which not only providesunusually large and stable gripping forces for securing the lamp holderassembly onto a supporting panel, but achieves such results by a onestep process from the front of the panel with the aid of merely a simpletool such as a screwdriver or Allen wrench.

When the assembly is assembled and mounted, a cent'ral, axiallyextending pin or rod member, which provides mechanical coupling from therear of the legend plate through the lamp holder assembly to the switchmechanism housed in the rear of the housing body, makes mechanicalcontact with a transversely disposed toggle sheet in front of the switchmechanism. The toggle sheet is snapped momentarily rearwardly by axialdisplacement of the pin member when the legend plate is depressed. Thetoggle sheet in turn makes mechanical contact with the electricalswitchmechanism in a manner to change its state of electrical connectionwhen the toggle sheet is snapped rearwardly. The toggle sheet featureembodied in the invention adds significantly to its mechanical andelectrical reliability and makes it possible to provide a multicolorswitch indicator which is less than half as deep in the direction normalto the mounting panel than are other such devices heretofore available.

Further details of these and other novel features, including the meansfor electrical connection within the assembly, for example, will becomeapparent and be best understood from a consideration of the followingde- 4 scription taken in connection with the accompanying drawing, inwhich:

FIG. 1 is a frontal elevational view of a switch assembly unitconstructed and mounted in accordance with the principles of the presentinvention;

FIG. 2 is a partially sectioned view of the structure of FIG. 1 takenalong the lines 22 therefor;

FIG. 3 and FIG. 4 are side elevational views of the structure of oneexample of the present invention illustrating certain steps in themounting and assembly thereof;

FIG. 5 is a side elevational view of the structure of the example of theinvention illustrated in the previous figures which is mounted but isopened as for inspection or relamping; 7

FIG. 6 is a sectional view of the structure illustrated in FIG. 1 takenalong the lines 6--6 thereof;

FIG. 7 is a frontal elevational view of an example of the inventionsimilar to that of the previous figures in which the legend plate hasbeen removed for purposes of illustration;

FIG. 8 is a sectional view of the structure of FIG. 7 taken along thelines 8-8 thereof;

FIG. 9 is a sectional view of an example of the invention which does notinclude an integral switching mechanism;

FIG. 10 is a perspective view of an alternative example of the presentinvention; and

FIG. 11 is a sectional view of a portion of the structure of FIG. 10taken along the lines 11-41 thereof;

Referring to the figures in more detail, it is stressed that theparticulars shown are by way of example only and are presented in thecause providing what is believed to be the most useful and readilyunderstood description of the principles and concepts of the invention.The detailed showing is not to be taken as a limitation upon the scopeof the invention which is defined by the appended claims forming a partof this specification.

In FIG. 1 a frontal view of a multicolor indicator switch actuatorassembly 20 is shown mounted on a panel 22. The unit includes a legendplate 24 having a front surface substantially coplanar with that of alegend plate retaining rim 26. The unit of this example is adapted toprovide a number of indication functions as by six different colors oflamps or three different double lamped colors each with two differentintensities. The switching actuation is accomplished, as indicated bythe legend on the plate 24, by depressing the legend plate 24 into theplane of the paper until a stop is reached or a positive switchingaction is felt.

In FIG. 2 a sectional view is presented, as indicated by the sectionedreference numerals 2-2 of FIG. 1, which shows the mounting panel 22 insection and the indicator switch assembly 20 in side elevation. Theexposed portions of the assembly 20 include the legend plate retainingrim 26. A mounting bracket 28 is illustrated having a rear portion 30disposed across the rear closed end of a housing body 32 and a pair ofside extension members 34, 36, which are disposed along a pair ofopposite sides of the housing body 32 and include outwardly bowedportions 38, 40, the latter being impressed compressively against therear surface of the mounting panel 22. The side extension members 34, 36extend forwardly through :the mounting panel 20 and are terminatedagainst the rear edge of a forward rim portion 42 of the housing body 32which defines a mounting shoulder 44. The inner cross dimension of theforward rim portion 42 is effectively slightly larger than the outercross dimension of the legend plate retaining rim 26 so that the lattermay fit snugly therewithin.

Projecting from the rear of the housing body 32 there is disposed aconnector portion 46 which includes conductive memberswhich mate withassociated ones carried within the mounting bracket 28. A connectingcable 48 may include flexible conductors which are connected to themating conductors within the mounting bracket 28.

Referring to FIG. 3 and FIG. 4, the assembly 20 is illustrated as thoughinterrupted during the process of mounting it through the mounting panel22, shown here in dotted lines. The mounting bracket 28 is shown asbeing substantially in position with its side extension members 34, 36extending through a mounting opening 50 and terminating at or near thefront surface of the mounting panel 22. The outward peak of the bowedportions 38, 40 are shown to be disposed just rearwardly of the rearsurface of the mounting panel 22. The housing body 32 is shown stoppedin the process of being inserted through the mounting opening 50 withinthe side extension members 34, 36 of the mounting bracket 28. In theprocess of mounting, the housing body 32 is moved through rearwardly asindicated by the motion arrows 52, 54 until its rear surface is closelycontiguous to or in contact with the front surface of the rear portion30 of the mounting bracket 28. In such final disposition, the mountingshoulder 44 extends beyond the extremity of the mounting opening 50 andcontacts the front surface of the mounting panel 22 about the entireperiphery of the mounting opening 50. The conductors 56 extending fromthe connector portion 46 are, when thusly mounted, inserted within andin contact with mating connectors within the rear portion 30 of themounting bracket 28.

When the housing body 32 is in this manner inserted through the mountingopening 50 and plugged into the mounting bracket 28, a pair of mountingscrews 58 are engaged by mating threads within the rear portion of themounting bracket 28 and are drawn up so as to compress tightly the frontextremity of the side extension members 34, 36 against the mountingshoulder 44 and increase the magnitude of outward bowing of theoutwardly bowed portions 38, 40. The latter, due to their compressivecontact with the rear edge of the mounting opening 50, urge the assemblyrearwardly and tightly bind the mounting panel 22 between mountingshoulder 44 and the outwardly bowed portions 38, 40. This processconstitutes the total effort required in the secure but removablemounting of the assembly 20 to the mounting panel 22. It remains merelyto insert a lamp holder assembly 60 into the housing body 32 through itsopen front end within the forward rim portion 42 as shown more clearlyin FIG. 5. The lamp holder assembly 60 is shown as including a pluralityof laterally extending lamp retaining bores 62 within each of which isshown disposed an indicator lamp 64, shown here with their contact endsprojecting outwardly from the central portion of the lamp holderassembly 60. The legend plate retaining rim 26 is disposed snugly overthe frontal portions of the lamp holder assembly 60 and is hingedlyaifixed thereto by a pin hinge 66 so that the legend plate retaining rim26 may be hinged downwardly and outwardly to form a retaining tray for ithe legend plate and to provide access, when desired, into the centralportions of the lamp holder assembly 60. It may be noted that relampingmay be accomplished without moving the retaining rim 26 with respect tothe lamp holder assembly 60, since the indicator lamps 64 may be removedfrom the side of the assembly behind and clear of the retaining rim 26.

With the assembly 60 is inserted into the housing body 32 a pair ofwithdrawal limiting clips 68, 70 which extend rearwardly from the sidesor top and bottom of the assembly 60 are engaged by matching clips, notshown in these figures, within the housing body 32. The clips 68, 70 arepreferably formed of spring metal, such as spring steel or berylliumcopper, for example, and are shaped to bow outwardly as shown so as toassure contact with the mating clips within the housing body 32 and toprovide ground electrical contact, when desired, between the assembly 60and the housing body 32.

In FIG. 5 the assembly 20 is shown mounted and assembled as in FIG. 2,except that the housing assembly 60 is shown withdrawn from the interiorof the housing Referring to FIG. 6, a vertical section taken through thecenter of the structure illustrated in FIG. 1 is presented. In this viewthe housing body 32 is shown in more detail and is indicated in thisexample as being.

fabricated of a non-conductive rigid, plastic. The cross dimension ofthe housing body 32 rearwardly of the forward rim portion 42 is seen tobe slightly smaller than that of the mounting opening 50 in the mountingpanel 22 in order to permit the passage therebetween of the forward endportion of the side extension members 34, 36 of the mounting bracket 28all shown in dotted lines. Again, the outwardly bowed portions 38, 40 ofthe side extension members are seen to be compressed outwardly andforwardly against the rear edge of the mounting opening 50 in a mannerto compress the mounting panel 22 firmly between the mounting shoulder44 and the outwardly bowed portions of the mounting bracket. Thus theentire assembly is held firmly at two spaced sets of contact regions,namely, that formed at the rear of the mounting shoulder 44 and thatformed by the contact with the outwardly bowed portions 38, 40 and themounting bracket.

The mounting screws 58 are seen to constitute tension members fordrawing the mounting bracket relatively forwardly against the housingbody 32. The forward rim portion 42 is seen here more clearly to form africtional receiving means for the legend plate retaining rim 26. Thefriction between the rim 26 and the forward rim portion 42 of thehousing body 32 is preferably made to be adequate by conventional meansto retain the assembly against accidental dislodgment. The frictionbetween the retaining rim 26 and the housing assembly 60 is made to havea magnitude so'that in spite of the drag by the clips 68, 70 and thebulb contacts, the entire assembly 60 will be withdrawn from the housingmember 32 when the retaining rim 26 is withdrawn from the rim portion42. Mating clips 72, 74 are disposed within the housing body 32 in aposition to engage the extending clips 68, 70 to limit the extent ofwithdrawal of the assembly 60 from the housing body 32. The withdrawinglimiting means may be defeated when desired by partially withdrawing theassembly 60, depressing the clips 68, 70 inwardly, and then withdrawingthe entire assembly all the way.

The lamp holder assembly 60 is shown in this figure to include a concavereflector surface 76. The indicator lamps 64 are fitted with coloredfilter caps thereover, indicated by G, R and A to signify that theircolors are green, red, and amber, respectively. The concave reflectorsurface 76 is contoured, as shown, about, in back of, and forwardly ofeach of the lamps 64 in a manner to reflect and project and dispersetheir illuminating energy forwardly toward the legend plate 24. A switchactuating rod 78 is disposed centrally through the assembly 60 by meansof a supporting opening 80 therein. The switch actuating rod 78 isadapted to be engaged, for longitudinal displacement, by the rearsurface of the legend plate 24 and to contact the switch actuator member82 of an electrical switch mechanism 84. In this example of theinvention, the positive toggle action of the switch mechanism 84 istransmitted back through the rod 78 so that the operator may feeldefinitely the changing of the switching state of the switch mechanism84. Resilient means for aiding in the return and orientation of thelegend plate 24 are provided in the form of small springs 86 disposedbetween the forward face of the assembly 60 and the rear surface of thelegend plate 24 and retained by small bores 88 formed perpendicularlyinto the face of the former.

The body of the assembly 60 may be formed of a metal, as indicated,which may be aluminum. In this case, the reflector surface 76 may bemade highly reflective simply by conventional finishing techniques.However, in other embodiments of the invention, the body of the assembly60 may be formed of a rigid plastic substance in a plurality of mountedsections and the reflector surface 76 formed by vacuum plating a brightmetal onto the surface of the plastic substance.

In FIG. 7 an example of the invention is illustrated in frontalelevation. An indicator switch unit 90 is shown mounted upon a mountingpanel 92. A legend plate retaining rim 94 is shown with its legend plateremoved in order to illustrate a frontal elevational view of a concavereflector surface 96 relieved from the front of a lamp holder member 98.Six indicator lamps 64 are shown projecting laterally into the cupformed by the reflector surface 96 and covered by a colored filter en-'velope as indicated by the letters G, R, or A. A switch actuating rod100 is shown end-on for mechanical communication between the legendplate and the switch mechanism, both not shown.

In FIG. 8 a horizontal sectional view of the structure shown in FIG. 7taken through its center is illustrated. A housing body 102 similar tothat shown in the previous figures, is disposed within a mountingopening 104 of a mounting panel 106. The mounting means and therelationships between the housing body 102, the legend plate retainingrim 94, and the lamp holder member 98 are substantially identical tothose discussed above in connection with the earlier figures.

A plurality of laterally directed bores 108 are provided in the lampholder member extending from opposite sides thereof into the cup formedby the reflector surface 96. A retaining shoulder 110 is provided ineach of the bores 108 near the reflector surface 96 for retaining thebase lip 112 of the plastic color filters as shown. A short, outwardlybiasing spring 114 is disposed within each of the bores 108 adjacentlyto the lip 112. An indicator lamp 64 may then be inserted from the sideof the lamp holder member 98 radially within the spring 114 and into thecolor filter until the mounting shoulder 116 engages the spring 114. Thespring 114 has a length which just firmly causes the central contact 118of the lamps 64 to contact a respective conductive strip 120 disposed onthe inner side surface of the housing body 102. Each of the conductivestrips 120 is provided with an inwardly raised portion 122 which forms,in cooperation with the central contact 118 of each of the lamps 64, aball and detent retaining means for positively securing the lamp holdermember 98 within the housing body 102. In addition to the positivefriction provided by this spring ball and detent system, a positive feelto the operator is provided for indicating when the lamp holder member98 has been properly inserted within the housing body 102.

The switch actuating rod 100 passes through and is supported by acentral bore 123 through the lamp holder member 98. The rearwardlydisposed end of the rod 100 may be terminated with a retaining end 124.

A toggle sheet 126 is retained under compression along its lengthbetween a pair of retaining channels, not shown in this view, in thesides of the housing body 102. The length of the toggle sheet 126 andthe orientation of its retaining channels are such that as retained bythe sides of the housing body 102 it bows forwardly, or outwardly, to apoint contiguous to the switch actuating rod 100. When the rod 100 isdepressed toward the rear of the housing body 102, it in turn depressesthe center of the toggle sheet 126 causing it to toggle to a low energyposition, indicated by the dotted lines, which although only a smallforce is required to hold it there, is not a stable position. Thus whenthe rod 100- is released and permitted to travel longitudinally backtoward the front of the unit, the toggle sheet 126 abruptly turns to itsnormal, forwardly bowed position.

A switching mechanism 128 which may be extremely compact and elementaryin form, because it need not include its own toggle mechanism, issecured in the rearward portion of the housing body 102. The switchingmechanism 128 includes an actuator 130 which is contacted and driven bythe toggle sheet 126 and which changes the state of the electricalswitch mechanism 128 at a point between the lower extremity of thetravel of the toggle sheet and its dead center position approximatelymidway between the two positions shown for the toggle sheet 126. By thismeans when the toggle sheet is depressed and the operator feels thetoggle action through the rod 100, he knows that the state of theelectrical switch mechanism 128 has been reversed.

In the example of the invention illustrated in FIG. 9, a multicolorindicator is shown partially in section which does not include switchingmechanisms. The structural features of this example of the inventionare, in most respects, substantially identical to those discussed abovein connection with the earlier figures, except that the entire unit maybe forshortened due to the absence of a switching mechanism. Inaddition, a raised, exposed portion of its indicator legend plate whichprotrudes through the legend plate retaining rim 142 may be different inshape from that of the previous examples. For example, the raisedportion and the frontal opening in the retaining rim 142 may be squareor triangular to indicate that the unit is an indicator as opposed tothe circular exposed portions of the legend plates of the previousexamples which may be round to indicate that their associated unit is aswitch indicator assembly. Further in the example of FIG. 9, a lampholder member 144, shown in side elevation may include a plurality ofindicator lamps 64 which make sliding ball and detent contact withelongated connecting strips 146 which communicate electrically with theelectrical connector portions at the rear of a housing body member 148and mounting bracket 150. Since no displacement of the legend plate 140is necessary in this example, it may be retained closely between thefront surface of the lamp holder member 144 and the inner surface of therim 142. Thus the entire assembly may be considerably shortened in depthand still exhibit all the indicator advantages pointed out above.

Referring to FIG. 10 and FIG. ll, an alternative example of theinvention is illustrated. In this example a housing body 152 is providedhaving a forward, enlarged rim portion 154 substantially similar to theconfiguration described above in connection with the previous examples.Here, the lamp holder assembly 156 includes withdrawal limiting andsupporting clips 158, 160. The ends of the clips 158, 160 are shaped toform an outwardly curved hook portion 162, 164 each of which is insertedthrough and are urged outwardly against the bight 166, 168,respectively, of a telescoping clip member 172. The clips 170, 172include a pair of parallel, straight portions as shown and areterminated by outwardly turned end elements 174 which fit withinchannels 176 and which permit the clips 170, 172 captively to slideforwardly to increase the degree of withdrawal of the-assembly 156 fromthe housing body 152. In addition, the diameter of the bight 168, 166 isadequate to permit the swivelling therewithin of the hook portions 162,164. In this manner the assembly 156 may be withdrawn from the housingbody 152 and, when fully extended, be swivelled as shown to permitaccess to the mounting screws 180 through aligned apertures 182 in thetoggle sheet 184.

In this manner the entire assembly may be mounted without ever removingany part or portion of the assembly. When the mounting screws have beendrawn up into the threaded openings 186 in a mounting bracket andconnector 188, the assembly 156 may be swivelled to a straightenedposition, and inserted fully into the interior of the housing body 152.After the clips 158, 160 have been substantially inserted, a ridge 190disposed on the outside surface of the clips 158, 160 engages the bight9 166, 168 and further insertion of the assembly 156 causes the clips170, 172 to be moved along the channels 176 toward the rear of the unit.

A plurality of rigid conductive strips 192 are secured to the innersurfaces of the housing member 152 and have extensions projectingthrough the body 152 to form male connectors for insertion within themounting bracket and connector 188. The toggle sheet 184 is relievedalong its end portions, as shown, to permit the passage of theconductive strips 192.

Referring more particularly to FIG. 11, the housing body 152 is shown insection with the conductive strips 192 secured to its inner surfaces andextending through the rear portion 194 thereof to form the maleconductive connectors. The toggle sheet 184 is also shown in section andis foraminated as indicated to permit access to the mounting screws 180and passage of the conductive strips 192 therepast. The retainingchannels 196 in the housing body 152 which were mentioned but not shownabove retain the toggle sheet 184 in the desire, forwardly inclined,buckled position.

A switching mechanism 198 is shown in block form and includes a holdingsolenoid 200 which may be wafer thin in a toroidal configuration and useas its armature the toggle plate or sheet 184 itself. In this case thetoggle plate must, of course, be fabricated from a paramagnetic metal.Because the depressed non-stable position of the toggle plate 184 is alow mechanical energy state for the toggle sheet, a very small holdingcurrent in the solenoid 200 is required to hold the toggle sheet in thatposition. In operation, when the switch actuating rod 202 is depressed,that is moved longitudinally toward the switching mechanism 198, thetoggle sheet 184 pops to its position against the holding solenoid 200and holds a switch actuating member 204 in its momentary contact statewhere it will remain for so long as the toggle sheet 184 is held in thedeformed position against the solenoid 200 either by electricalenergization thereof or by a maintained depression of the rod 202 by theoperators digit.

There has thus been disclosed a number of examples of a multicolorindicator switching unit in accordance with the present invention whichachieve the objects and exhibit the advantages set forth above.

What is claimed is:

1. Mounting assembly of the character to be secured within an apertureon a mounting panel and comprising:

a thin-walled housing body having rear and side surfaces, a frontsurface, and a mounting rim disposed about the periphery of said frontsurface, said rim defining a mounting shoulder along its rear edge forcontacting the front surface of said panel contiguously to the peripheryof said aperture;

a mounting bracket having a rear portion adapted to be disposed acrosssaid rear surface of said housing body and having side members extendingalong said side surfaces of said housing body, said side members eachhaving a bowed-out portion disposed contiguously to the rear of saidpanel when said assembly is mounted;

the length of said side members being greater than that of said sidesurfaces of said housing body and having a forward end which, when saidassembly is mounted, terminates against said mounting shoulder; and

securing means for drawing said rear portion of said mounting brackettoward said rear surface of said housing body and urging said forwardends of said side members compressively against said mounting shoulderthere-by tending to increase the magnitude of bowing of said bowed-outportion and bind said panel securely between said bowed-out portions andsaid mounting shoulder.

2. Mounting assembly of the character to be secured within an apertureon a mounting panel and comprising:

a thin-walled housing body having rear and side surfaces, a frontsurface, and a mounting rim disposed about the periphery of said frontsurface, said rim defining a mounting shoulder along its rear edge forcontacting the front surface of said panel contiguously to the peripheryof said aperture;

a mounting bracket having a rear portion adapted to be disposed acrosssaid rear surface of said housing body and having side members extendingalong said side surfaces of said housing body, said side members eachhaving a bowed-out portion disposed contiguously to the rear of saidpanel when said assembly is mounted;

bracket engaging means carried by said housing 'body contiguously to itssaid front surface, the length of said side members being at leastapproximately as great as that of said side surfaces of said housingbody and having a forward end which, when said assembly is mounted,terminates against said bracket engaging means; and

securing means for drawing said rear portion of said mounting brackettoward said rear surface of said housing body and urging said forwardends of said side members compressively against said bracket engagingmeans thereby tending toincrease the magnitude of bowing of saidbowed-out portion and bind said panel securely between said bowed-outportions and said bracket engaging means.

References Cited UNITED STATES PATENTS 1,662,422 3/1928 Hodges 2203.61,750,061 3/1930 Smith et al. 2203.6 1,779,681 10/1930 Smith et al.2203.6 1,861,400 5/1932 Miller.

2,604,285 7/1952 Knoch 2203.6

THERON E. CONDON, Primary Examiner.

JAMES R. GARRETT, Examiner.

